I shall discuss failure of naturalistic ethical theories to satisfy two requirements for an adequate
ethical theory: on the one hand, the arguability requirement, which is that an ethical
theory should do something to resolve moral disagreements by the use of argument; on the
other hand, the practicality requirement, which is that an ethical theory should be able to
account for the necessary relation between morality and action – by which I mean the capacity
moral judgments have to provide everyone with justifying reasons for action. Such
two limits of naturalism will be examined by considering Iris Murdoch’s and John
McDowell’s views about ethics. The former are centred around the notion of moral vision,
as opposed to choice and action; the latter are focused on the notion of moral sensibility.
While putting forward two different forms of naturalism, Murdoch and McDowell agree
that descriptive and evaluative meanings of ethical terms are not independent of one another,
and that people who make conflicting moral judgments about something do see different
facts. Moreover, both Murdoch and McDowell hold that moral reality is much more
complex than reality which is investigated by natural sciences.